| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.06 |
| Score | 0% | 61% |
The combustion chamber is enclosed by the:
head gasket |
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piston ring |
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piston |
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cylinder head |
Cylinders act as a guide for the pistons that translate the heat energy of combustion into the mechanical energy necessary to move a vehicle. Piston rings seal the piston to the cylinder to contain combustion gases and also regulate the oil distribution between the piston and cylinder wall. A cylinder head closes in the top of the cylinder forming the combustion chamber which is sealed by a head gasket (head). The head provides space for air and fuel intake valves, exhaust valves, and mounts for spark plugs and fuel injectors.
Just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. This describes which engine stroke?
exhaust |
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intake |
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power |
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compression |
During the power stroke, just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. The resulting expansion due to combustion pushes the piston back down the cylinder toward bottom dead center.
Too much air results in a __________ air-fuel mixture that burns more slowly and hotter.
light |
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rich |
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lean |
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heavy |
The stoichiometric ratio defines the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air. For gasoline fuel, the stoichiometric ratio is about 14.7:1 or for every one gram of fuel, 14.7 grams of air are required. Too much air results in a lean air-fuel mixture that burns more slowly and hotter while too much fuel results in a rich mixture that burns quicker and cooler.
Which of the following is not a component in the engine lubrication system?
pressure relief valve |
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pickup tube |
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differential |
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oil filter |
In engine lubrication, oil remains in the oil pan until the engine is turned on. It then gets sucked up the pickup tube by the oil pump and pressurized. This pressure is moderated by the pressure relief valve and the oil is fed through the oil filter into the engine to lubricate it.
What cylinder arrangement would be most common in a four cylinder front-wheel drive vehicle?
opposed |
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V-type |
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inline |
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vertical |
Cylinder number and arrangement depends on the purpose of the engine. Smaller (four and six cylinder) engines in front-wheel drive vehicles often use an inline design which orients cylinders vertically over the crankshaft and aligns them in a row. Other common orientations are a horizontal/opposed design which places cylinders flat facing each other with the crankshaft between them and a V-type design common in six and eight cylinder engines that features one cylinder head per block of cylinders oriented at a 60 to 90 degree angle to each other with the crankshaft at the bottom of the V.